Flux Rope Eruption and Associated Vertical Prominence Oscillation

We present a plane-of-sky observational analysis of a solar eruptive event that occurred on 2 September 2023. The flare peaked at approximately 07:00 UT, closely aligning with the impulsive acceleration phase of the erupting flux rope, which accelerated from an initial speed of 42 km s−1 to 501 km s−1. The associated coronal mass ejection (CME) propagated through interplanetary space at a near-constant speed of 519 km s−1, suggesting that its kinetic energy was primarily acquired within the lower solar atmosphere. Comparison of the projected propagation directions of the erupting flux rope and the CME reveals an apparent angular offset of approximately 10°, which is interpreted through Potential Field Source Surface (PFSS) modeling as the result of asymmetric magnetic pressure gradients. Notably, the overlying coronal loops exhibited a piecewise acceleration, with the velocity increasing from approximately 7 km s−1 to 320 km s−1. Furthermore, the passage of the eruption-induced disturbance triggered large-amplitude, damped vertical oscillations in an adjacent prominence. Applying magnetohydrodynamic (MHD) prominence seismology based on Hyder’s model, we derive a local radial magnetic field strength of 1.77–7.02 G. These results provide a detailed view of the evolution from magnetic energy release to large-scale coronal disturbances and the subsequent prominence oscillation.